Joing a Zwift event late resulted in doing one more lap


Today I joined my first Zwift event (Tour de Zwift - Stage 1). Took me few minutes to understand when the ride would start so started riding with the group 2min late or so. What I noticed was that the distance on the 1st lap was not coming down, after I passed the finish line and joined the 2nd lap all was good. So in the end I had to complete 48km to finish of the 3 laps instead of 37km that was the 3 laps and everyone else did.

Is this normal?